ASoC: fix soc-core.c kernel-doc warning

Fix kernel-doc warning:

../sound/soc/soc-core.c:2918: warning: Excess function parameter 'legacy_dai_naming' description in 'snd_soc_register_dais'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Mark Brown <broonie@kernel.org>